Keck Medicine Dermatologists Tackle the Toughest Skin Problems

Skin can be your body's first line of defense against disease. Here's how physicians keep it healthy.

When David Peng was training to be a physician, he wanted nothing less than to save the world. It was the 1990s, and young doctors-to-be were vying to enter hot fields. A flurry of advances in device technology and the artificial heart led some to cardiology. Others aimed to save lives through desperately needed AIDS research.

During a dermatology rotation, an attending physician urged Peng to consider a different route.

In dermatology, a subspecialty that many choose for its reasonable hours and lucrative pay, Peng would face less research competition than in other fields, the physician told him. “He says, ‘You’d be a big fish in a small pond—and you’d have a greater impact if you did,’” Peng recalls.

Fast forward two decades, and he’s making a difference as the contagiously enthusiastic chair of the Department of Dermatology at the Keck School of Medicine of USC. Four years after Peng’s arrival from Stanford University, the department has tripled in size to 18 physicians, with new hires recruited from top residency programs like Harvard University and University of California, San Francisco. They’ve brought with them a zeal for combining patient care with research, both clinical and lab-based. Keck Medicine of USC dermatologists today are making advances against melanoma and other skin cancers, psoriasis, allergic reactions and even leprosy. As for Peng, his original goal has evolved into a more defined, if no less audacious, one for Keck Medicine dermatology. “We are going to go as far as science can carry us,” he says.

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SKIN’S HEAVY LOAD

To listen to Peng, you’d think there was no more exciting organ in the body than the skin. Yes—it’s an organ. Skin isn’t just the body’s largest organ, but its heaviest. “We used to think it was just a bag, essentially, that kept everything intact,” Peng says. Today physicians see it as the body’s first line of defense.

David Peng, Chair of Dermatology

The skin has lots of duties, as he explains. It’s a barrier that prevents disease. It’s also an early alert system for trouble, thanks to circulating immune cells that help the body fight off early signs of infection. Of course, it’s a vehicle for our sense of touch. And it provides a home for bacteria that can influence and alter the body’s immune system.

But with responsibilities come problems, and skin can suffer from a variety of them.

Peng’s own research focuses on melanoma, the deadliest form of skin cancer, and on the genetics of people who develop severe drug rashes, trying to identify patients who should avoid certain medicines. But these days, his primary concern is the welfare of his department.

“Every good chair considers the department’s success to be their metric for their own personal success,” he says. “I root for my faculty and I try to give them the opportunity to do well.”

Advances in treatment come from rigorous science, so Keck Medicine dermatologists are encouraged to dive into research. It’s a philosophy that sits well with members of the physician team.

The Experts

For dermatologist Ashley Crew MD ’09, her research focus means she gets the chance to study a topic that could help countless patients: how the internet can increase access to dermatology care, particularly among underserved populations. Los Angeles County uses a program called eConsult, which allows specialists to offer long-distance consultations to primary care physicians across the county. Crew is part of a team of researchers investigating the effort’s success in caring for skin problems and how it can be tweaked to further improve care and outcomes for patients.

She’s also co-chair of a multidisciplinary dermatology-rheumatology clinic. The clinic began as a way to treat patients with psoriasis, a common, chronic skin condition characterized by scales and dry, pink patches. But many psoriasis patients also suffer from arthritis — a rheumatologic disease. Now the multidisciplinary clinic allows people with a wide spectrum of rheumatologic conditions to be seen by physicians from both dermatology and rheumatology, helping patients “get a cohesive plan in place for their treatment,” Crew says.

MYTHS ABOUT SKIN CARE

Thanks to the internet and their own curiosity, patients today often present their physicians with self-diagnoses or ask about questionable medical theories. Here are some myths that USC dermatologists find themselves repeatedly dispelling:

“I don’t use sunscreen because I’m afraid it will give me cancer.” No, no, no, Ashley Crew says. “Sunscreen is one of the most important tools in preventing skin cancer.” But it’s also not a suit of armor. Apply it early and often, choose broad spectrum with SPF 30 or higher, wear protective clothing and grab shade when you can.

“It must be good for me—it’s organic.” Just because a cream or an eyeliner is made from natural ingredients doesn’t mean you can’t have an allergic reaction to it. “A lot of plant-based products are common culprits for causing skin rashes,” Crew says.

“I’m not at risk for melanoma because I only went to a tanning booth once.” Even one visit seriously increases the risk of developing melanoma, Binh Ngo says. “The majority of my melanoma patients in their 20s and 30s got it from tanning beds.”

“Cutting dairy will help my acne.” Actually, there haven’t been enough studies done on nutrition and skin because, as David Peng says, “who would fund it?” Most dermatologists don’t believe food can affect conditions like acne or eczema, he adds, “but if the patient swears it, then we always say if you believe that, then just avoid it.”

The clinic’s work is buttressed by research done by fellow Keck Medicine dermatologist April Armstrong. A graduate of Harvard Medical School, Armstrong did stints at the University of California, Davis and the University of Colorado before Peng recruited her in 2015. Part of her psoriasis research examines whether the skin condition is also a sign of internal issues. “We’ve found that patients with severe psoriasis have increased risk of heart attacks, strokes and death related to their cardiovascular system,” says Armstrong, who is associate dean of clinical research for the medical school and director of the psoriasis program. “We’re working to see if any of our current therapies can change that systemic inflammation.”

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BRAIN POWER

Another major area of dermatology research is skin cancer, and Peng isn’t alone at USC in targeting it. Dermatologist Binh Ngo studies genetic mutations in melanoma, trying to predict important characteristics such as its likelihood to recur or spread — or whether genetic mutations alone can point out whether a mole is cancerous or benign.

Ngo also looks at the incidence of skin cancers in organ transplant patients. Basal cell cancer is the most common form of skin cancer in the general population. But in transplant patients, due to immunosuppression, more-aggressive squamous cell cancer is seen up to 250 times more than in the general population. These carcinomas usually appear several years after transplantation, she says. Most at risk? Caucasian patients, because their skin has fewer protective, pigment-producing cells called melanocytes, and heart transplant patients, because they take the most immunosuppressant drugs.

Then there’s a disease that many think no longer exists: leprosy, also known as Hansen’s disease. Every year, about 200,000 people worldwide are diagnosed with the infectious disease, and it’s a specialty of dermatologist Maria Teresa Ochoa, who runs Keck Medicine’s leprosy clinic. The clinic is one of only three of its kind in the state and the largest in the nation, tracking several hundred cases of the disease.

The trick to treating leprosy patients, Ochoa says, is early diagnosis. “If they come to the clinic in time, they are going to be fine,” she says. “There are a lot of misconceptions, like is it very contagious? No, it is not very contagious. And there is treatment.”

Keck Medicine of USC dermatologists don’t just treat melanoma. They also study the cancer to better prevent it and improve therapies. This image taken through a microscope shows how deeply melanoma can grow beneath the surface of the skin.

Peng likes to talk about the brainpower and dedication of the physicians around him, such as Ochoa, but it’s clear from talking to them that he’s the department’s lodestar. Ochoa and Ngo praised Peng’s determination to help faculty members turn research ideas into reality. “Sometimes, in an academic institution, you may have the idea for something, but you just can’t make it happen,” Ngo says. “He’s a very strong supporter.”

Crew, who was mentored by Peng as a student, credits him with her choice of specialty. “If you did a survey of dermatologists in my generation,” she says, “I think there are many dozens of us who went into dermatology because of Dr. Peng. … His passion, enthusiasm and desire to push the specialty forward is infectious.”

And Armstrong calls him “the main reason I’m at USC.” Peng, she says, “is a terrific chair, passionate and compassionate. … He always asks what he can do to make our job easier.”

The hope, Peng says, is to make more possible: more quality clinic time, more opportunities for lab and clinical research. There are plenty of dermatologists who can treat common skin conditions and do cosmetic procedures and surgeries, he says. Keck Medicine’s dermatology group aspires to more. “We want to be thought leaders,” he says. “We want to be research leaders.”

So he invests time and resources in the recruitment and support of top dermatologists from around the country. Together, he says, Keck Medicine skin specialists can focus on treating — and solving — the toughest cases. Says Peng: “We want to be the referral point for anyone who doesn’t know the answer for one of their patients. … We’ll be the dermatologists for dermatologists.”

FIVE SKIN WARNING SIGNS

Our skin changes all the time: a pimple here, a rash there. But when is a skin issue a hint of a deeper problem? Here are a few signs that you might want to schedule an appointment with a dermatologist:

A butterfly rash on your face could be a sign of lupus, an autoimmune disorder. The technical term is “photodistributed erythema.” The rash spreads across the cheekbones and nose with sun exposure. “It looks like a butterfly in the middle of your face,” David Peng says.

Brown, thickened, velvety patches on the back of the neck could be a sign of diabetes. The name for the condition is “acanthosis nigricans,” and when Peng notices it on a patient, “oftentimes I can tell if someone is pre-diabetic before they even get their lab [results] back,” he says.

A changing mole deserves attention. Note if a mole grows or shrinks, changes color or suddenly appears where no mark existed before. This could indicate the potential for developing into melanoma.

Blotchy skin that loses sensation could be the first indicator of leprosy. Symptoms begin with “a small redness,” Maria Teresa Ochoa says. Then patients lose the feeling on that patch of skin. But don’t be afraid of leprosy—today the disease is highly treatable.

A blistering rash could signal a herpes infection, April Armstrong says, or it could be “a really bad drug reaction.” Either way, don’t wait to get it checked out.